Reinforced ceramic matrix composites having fibers dispersed in continuous ceramic matrices of the same or a different composition are well suited for structural applications because of their toughness, thermal resistance, high-temperature strength, and chemical stability. Such composites typically have high strength-to-weight ratio that renders them attractive in applications in which weight is a concern, such as in aeronautic applications. Their stability at high temperatures renders them very suitable in applications in which the components are in contact with a high-temperature gas, such as in gas turbine engine.
Ceramic matrix composites are quite expensive because their typical production process is rather involved. Therefore, it is desirable to have a method of modifying such pieces, which may be damaged either accidentally or during use, such that they may be salvaged or their useful life may be extended.
Conventionally, damage to composites is repaired with externally bonded patches, which rely solely on bonding to the outer surface of the composite article. Unfortunately, these types of modifications do not engage enough of the base of the composite article to form a significant bond to the patch. Other methods of modification utilize a rivet or outer and inner plug halves which are joined together to create a floating patch that, again, does not directly bond to the composite article.
Thus, a need exists for improved methods for modifying a composite article.